While that's hilarious, it's funny (IMO) because of the setup during the episode.

In case you missed it, before the first commercial Kyle says to Stan "Just be careful you don't end up naked and jackin' it in San Diego." then walks away And Stan says "What the hell does that mean?" Then before the second commercial Kyle says "But when you're naked and jackin' it in San Diego, don't ask me for help." then leaves again. And Stan says "Why does he keep saying that?"

We have been singing that song nonstop since we saw the episode and have clear knowledge what it is about.
Still a good song!
Trey Parker is far better at writing music than he is anything else and IMO that's saying something.